1. Field of the Invention
The present invention relates to an imaging head, an imaging device and an imaging method, and particularly to an imaging head which relatively moves, with respect to an imaging surface, in a predetermined direction along the imaging surface, an imaging device which is equipped with this imaging head, and an imaging method which employs this imaging head.
2. Description of the Related Art
Heretofore, as examples of imaging devices, various exposure apparatuses which employ spatial light modulation elements such as digital micromirror devices (DMD) for implementing image exposure with light beams modulated in accordance with image data have been proposed.
An example of a DMD is a mirror device in which a plurality of micromirrors, which alter angles of reflection surfaces thereof in accordance with control signals, are arranged in a two-dimensional arrangement of L columns by M rows on a semiconductor support of silicon or the like. Practical exposure can be implemented by scanning the DMD in a certain direction along an exposure surface.
Generally, the micromirrors of a DMD are arranged such that directions of alignment of the respective columns intersect with directions of alignment of the respective rows. By disposing such a DMD to be inclined with respect to a scanning direction, a spacing of scanning lines at a time of scanning can be made tighter, and resolution can be raised. For example, Japanese National Publication No. 2001-521672 discloses that resolution can be raised, in an illumination system which guides light toward sub-regions (spatial light modulation elements) which are equipped with a plurality of light valves, by inclining these sub-regions with respect to projections thereof onto scanning lines.
However, fine adjustment of respective inclination angles of spatial light modulation elements is generally difficult, and the inclination angles will vary slightly from ideal angles. The spatial light modulation elements implement scanning, for example, row by row (or in units of a number of rows). However, when the above-mentioned variation occurs, the spacing of a pitch between rows when moving from a row to a next row becomes irregular, and unevenness in images is caused by gaps and/or overlaps.
In order to prevent such unevenness of images, it is considered that accuracy of the inclination angles of the spatial light modulation elements should be improved. However, production costs increase when improvements in accuracy are sought.
Similar problems can occur not only with imaging heads that employ spatial light modulation elements, but also with, for example, inkjet recording heads which implement imaging by ejecting ink droplets at an imaging surface.